From: a.ryabinin@samsung.com (Andrey Ryabinin)
To: linux-arm-kernel@lists.infradead.org
Subject: [RFC/PATCH -next 00/21] Address sanitizer for kernel (kasan) - dynamic memory error detector.
Date: Tue, 15 Jul 2014 18:32:23 +0400 [thread overview]
Message-ID: <53C53B77.3080000@samsung.com> (raw)
In-Reply-To: <alpine.DEB.2.11.1407141012520.25405@gentwo.org>
On 07/14/14 19:13, Christoph Lameter wrote:
> On Sun, 13 Jul 2014, Andrey Ryabinin wrote:
>
>>> How does that work when memory is sparsely populated?
>>>
>>
>> Sparsemem configurations currently may not work with kasan.
>> I suppose I will have to move shadow area to vmalloc address space and
>> make it (shadow) sparse too if needed.
>
> Well it seems to work with sparsemem / vmemmap? So non vmmemmapped configs
> of sparsemem only. vmemmmap can also handle holes in memory.
>
>
Not sure. This sparsemem/vmemmap thing is kinda new to me, so I need to dig some more
to understand how it i?teracts with kasan.
As far as I understand the main problem with sparsemem & kasan is shadow allocation:
unsigned long lowmem_size = (unsigned long)high_memory - PAGE_OFFSET;
shadow_size = lowmem_size >> KASAN_SHADOW_SCALE_SHIFT;
shadow_phys_start = memblock_alloc(shadow_size, PAGE_SIZE);
If we don't have one big enough physically contiguous block for shadow it will fail.
prev parent reply other threads:[~2014-07-15 14:32 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-09 11:00 [RFC/PATCH -next 00/21] Address sanitizer for kernel (kasan) - dynamic memory error detector Andrey Ryabinin
2014-07-12 0:59 ` H. Peter Anvin
2014-07-13 10:39 ` Andrey Ryabinin
2014-07-14 15:13 ` Christoph Lameter
2014-07-15 14:32 ` Andrey Ryabinin [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=53C53B77.3080000@samsung.com \
--to=a.ryabinin@samsung.com \
--cc=linux-arm-kernel@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).